Zigzag stitch-forming mechanism for sewing machines



Feb. 8, 1938. E, ALLEN AL 2,107,271

ZIGZAG STITCH FORMING MECHANISM FOR SEWING MACHINES Original Filed Nov. 10,' 1956 4 Sheets-Sheet l ZYVUMM Edward B/V/en, Deceased v Josephine WAl/en, Admx. wave: Maurice D. Knox, and

Harold C. Hau/kner' Feb. 8, 1938. E. B. ALLEN ET AL ZIGZAG STITCH FORMING MECHANISM FOR SEWING MACHINES Original Filed Nov. 10, 1936 4 Sheets-Sheet 2 lllllllllllllllllllll wan.

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Feb. 8, 1938. E. B. ALLEN ET AL 2,107,271

ZIGZAG STITCH FORMING MECHANISM FOR SEWING MACHINES Original Filed Nov. 10, 1956 4 Sheets-Sheet 3 3 wuc/wfm Edward 5. A//en, Deceased mi-Mesa xbsep/v/ne W/V/en, Aa'mx.

Maurice D. ffi-rox, and W N. CM

Feb. 8, 1938. E. B. ALLEN ET AL.

zmzm STITCH FORMING MECHANISM FOR SEWING MACHINES 4 Shets-Sheet 4 g wuemm- Deceased \bse Qhine W/V/en, Adm) Maurice D hfvox,

Original Filed Nov. 10, 1956 Edward B. Alfie/1.

a ld Harp/cl (2.. Fau/lrner Patented Feb. 8, 1938 UNITED STATES PATENT OFFICE ZIGZAG STITCH-FORMING MECHANISM FOR SEWING MACHINES Original application November 10, 1936, Serial No. 110,026. Divided and this application which, although of general utility in the zigzag The hollow needle-bar I3, Figs. 12 and 13, has 5 lock-stitch sewing machine art, is adapted more fixed to its lower end the yoke I4 carrying the particularly for use in a lock-stitch buttonhole cross-pin I5 on which is slidably mounted the sewing machine such as disclosed in our copendneedie-clamp-block I6 having at its upper end ing application, Serial No. 110,026, filed Nov. 10, a guideway II, Fig. 11, embracing the horizon- 10 1936, of-which this application is a division. tal member of the yoke I 4. The block l6 car- 10 With the above and other objects in view, as ries the eye-pointed needle Ill. The yoke I4 is will hereinafter appear, the invention comprises slidably received at one end in the guideway I9, the devices, combinations and arrangements of Figs. 12 and 14, in a Vertical a 10 depending parts hereinafter set forth and illustrated in the from a block 2| fixed to the lower end of the 15 accompanying drawings of a preferred embodineedle-bar-bearing bushing 22 journaled in the 15 ment of the invention, from which the several head 4 and having the pinion 23 fixed to its upper features of the invention and the advantages end, whereby turning movements may be imattained thereby will be readily understood by parted to it, as in stitching around the eyeletthose skilled in the art. end of a buttonhole.

In the accompanying drawings'Fig. 1 is a right The block 2I also has depending from it an- 20 side elevation of a buttonhole sewing machine other arm 24 which is spaced from the arm 20. embodying the invention. Fig. 2 is a vertical sec- The arms 24 and 20 carry a cross-pin 25 on which tion taken longitudinally of the machine bed is horizontally slidably mounted a vertical guidethrough the shuttle mechanism mounted therearm 26 having a guideway 21 receiving the 25 in. Fig. 3 is an elevation of the parts shown in spaced rearward extension 28 of the needle- 25 Fig. 2 looking from the right. Fig. 4 is a verticlamp-block l6. The guide-block 26 is steadied cal section through the shuttle-carryingturret on the cross-pin 25 by having its upwardly exlooking at the face of the shuttle. Fig. 5 is a tending end 29 slidably received in a guldeway section on the line H, Fig. 2. Fig. 6 is a sec-. 30, Fig. 11, in the block 2|; said guideway be- 30 tion on the line 6-4, Fig. 4. Fig. 7 is a section ing completed by the cover-plate 3I. The needle 30 on the line '|--'l, Fig. 4. Fig. 8 is a detail view I8 is thus supported for endwise reciprocatory of the pin and star-wheel drive through which and laterally vibratory movements in a rotary the needle-vibrating mechanism is actuated. support which is tumable about a verticalaxis. Fig. 9 is a side elevation of the needle-vibrating The vertical guide-block 26, which imparts the mechanism. Fig. 10 is a section on the line lateral vibratory movements to the needle- 35 ll-III, Fig. 9. clamp-block I6, is connected by a link 32, Fig. 9,

Fig. 11 isa vertical section on the line II 'll, of adjustable length to an arm 33 fixed to one Fig. 9. Fig. 12 is a section on the line I2-I2, end of a rock-shaft 34 journaled in the block Fig. 11. Fig. 13 is an elevation of the lower endand having fi to s other end a a 3 of the needle-bar showing the yoke and needle- Fig. which pivotally Carries & ck 5 4o clamp-block. Fig. 14 is a perspective view of received in the circular groove 31 in the ring the rotary needle-bar bushing, and Fig. 15 is a member 38 fixed to the lower end of the vertical perspective view of the laterally reciprocatory slide-rod, Fig. 1, journa1ed in the head I. The guide-block for the needle-clamp-block. ring 38 is steadied by the fixed guide-pin 40 The machine frame comprises the hollow boxwhich it slidably engages. Thus, vertical move- 45 like bed I from one end of which rises the standments of the slide-rod 39 and ring 38, impart ard 2 of the overhanging bracket-arm 3 termilateral vibratory movements to the needle It in nating in the head 4. any position of the plane of vibration of the Joumaled within'and lengthwise of the bed latter.

I, is the main sewing shaft 5, Fig. 1, which, Therod 39 is reciprocated vertically, to impart 50 through the one-to-one bevel gears 15, 1, drives lateral vibratory movements to the needle l9, by the vertical shaft 8 journaled within the standthe following mechanism. Fixed to the rod 39 ard 2. The shaft 8 has a one-to-two speedis a block 4|, Fig. 1, which extends laterally multiplying bevel-gear driving connection 9' with through a slot 42 in one side wall of the head l and has pivotally connected thereto one end 01' 55 March 18, 1937, Serial No. 131,618

has for an object to provide an improved and simplified zigzag stitch-forming mechanism, including loop-taker-compensating mechanism,

the upper or needle-bar-reciprocatlng shaft III which is journaled'within and lengthwise of the bracket-arm 3 and has the usual crank I I and link-connection l2 with the vertically reciprocatory hollow needle-bar I3 mounted in the head I.

a link 43 the other end of which is adjustably and pivotally secured in the slotted segmental arm 44 of a bell-crank lever 44. 45 fulcrumed at 48 on the head 4. The arm 45 of the bellcrank lever is connected by the link 41 to the adjustable crank-pin 48 projecting from the outer face of a crank-head 49 pivoted at 50, Fig. 1, on the disk-shaped head 5I, at one end of the shaft 52 journaled within and transversely of the bracket-arm standard 2.- ,Movement of the crank-head 49 about the pivot-screw 50 changes the eccentricity or operative radius of the crank 48 relative to the axis of its drive-shaft 52.

This adjustable crank mechanism is built substantially in accordance with the disclosure in the Allen et al. application, Serial No. 759,200, filed Dec. 26, 1934, and need not be specifically described herein. It will sufilce to explain that the shaft 52 carries a bevel pinion 58 which is driven by the bevel gear 54 fixed to the vertical shaft 55, Figs. 1 and 8,-carrying at its lower end a pinion 56 driven by a gear 51 fixed to the vertical stub-shaft 58 to which is also fixed the starwheel 59 driven by the diametrically opposed pins 60 at the lower end of the vertical shaft 8. The pin and star-wheel drive imparts intermittent rotary motion to the shaft 55, which, in turn, im-

parts intermittent semi-rotational impulses to the crank 48 which actuates the needle-vibrating mechanism above described.

Detachably mounted on the transverse framemember 8 I, within the bed I, is the turret carrier block 62 having the upper and lower spaced bearings 63, 54 for the tubular stem 55 of the turret 66 carrying the yieldingly separable shuttle race rings 61, 68, Fig. 6, in which is journaled the conventional sewing machine shuttle 69 carrying the usual bobbin I0, Fig. 2, of under thread. The shuttle i9 is oscillated in its raceway by means of a shuttle driver II of usual form which is carried by the shaft I2 journaled in the bearing I8 at the rear of the turret 65. The shaft I2 has pinned to it a pinion I4 meshing with the sector gear 15 fixed to one of the trunnions I8, Fig. 7, of

the rocking sleeve I'I journaled in the turret 86. The sleeve II is entered by the pin I8 the bifurcated head I8 of which is pivoted at 80 to the upper end of the reciprocatory rod 8I slidable in the turret stem 85.

Screwed to the longitudinally ribbed face 82, of the rod 8I are two spaced gibs 88 which extend outwardly through the slot 84 in the tubular stem 85 of the turret and embrace the ring member 85 which surrounds the stem 65. The ring member 85 is carried by the slide-plate 88 guided in the vertical guide-way 81 in the turret-carrier block 82. The slide-plate 88 has .a stud-pin 88 projecting rearwardly therefrom and this stud-pin is connected by the pitman 89 to the crank 90 on the shaft 9| journaled in the carrier 92 which, in turn, is journaled on the bearing bushing 93 in which the main sewing shaft 5 is journaled. The bushing 83 is set into an aperture 04 in the frame member SI. The shaft SI has fixed to it a pinion 95 driven by the gear 86 of double its size on the 7 main shaft 5.

In order to compensate the shuttle mechanism for the different lateral positions of the laterally vibratory needle, provision is made to accelerate and retard the shuttle-driving shaft 9| so that the shuttle beak will be properly timed relative to the needle in the different lateral positions of the needle. To this end there is mounted on the main sewing" shaft 5 an eccentric III' embraced by the eccentric-follower lever 88 the forked lower end of which slidably embraces the anchor-block 99 fixed to the rockable pin I journaled in the frame block IOI secured to the frame cross-meme ber 6 I The upper forked end of the lever 98 embraces the block I02 rotatively free on the shaft III and confined between the collar I03, Fig. 2, and the head of the screw I04. Thus, rotation of the main shaft imparts oscillatory movement to the carrier 92 for the crank-shaft SI which latter is given two rotations for one complete to-and-fro oscillation of the carrier 02.

The shuttle thread is delivered through the apertured end of the thread-case arm I05 in which the bobbin I0 is housed; the arm I05 being freely received in the notch I06 in the plate I01 screwed to the outer shuttle race ring 68 which is pressed by the springs I08 against the inner shuttle race ring 61. The thread-case is thus restrained from oscillating with the shuttle 59. There is mounted on the vertical back-plate of the shuttle race the shank I09 of the buttonlike needle-throat member 0' formed with the needle-receiving slot III. The needle-throat member supports the work against the thrusts of the needle.

The turret and needle-bar rotating bushing are coaxially mounted and are turned in unison by the usual means, to position the stitches radially around one end, for example, the eyeletend of the buttonhole; such means being disclosed, for example, in U. S. Patent No. reissued Apr. 4, 1922, and in our said copending application.

Having thus set forth the nature of the invention, what we claim herein is:-

1. In a lock-stitch sewing machine, the combination with a reciprocatory and laterally vibratory needle, of a circularly moving loop-taker, a bobbin, 'a rotary driving shaft, 9. driving gear carried thereby, a driven shaft, a pinion of half the size of said driving gear mounted on said driven shaft and meshing with said driving gear, a carrier for said drivenshaft mounted for oscillatory, movement about the axis of said driving shaft, means on said driving shaft and connections to oscillate said carrier, and means actuated by said driven shaft for imparting circular movement to said loop-taker.

2. In a lock-stitch sewing machine, the combination with a reciprocatory and laterally vibratory needle, of a circularly moving loop-taker, a bobbin, a rotary driving shaft, a driving gear carried thereby, a driven shaft, a pinion of half the size of said driving gear mounted on said driven shaft and meshing with said driving gear, a carrier forsaid driven shaft mounted for oscillatory movement about the axis of said driving shaft, an eccentric on said driving shaft, a vibratory lever actuated by said eccentric and connected to impart oscillatory movement to said carrier, and means actuated by said driven shaft for imparting circular movement to said looptaker.

3. In a lock-stitch sewing machine, the combination with a reciprocatoryand laterally vibratory needle, of a circularly moving loop-taker, a bobbin, a rotary driving shaft, a driving gear carried thereby, a driven shaft, a pinion of half the size of said driving gear mounted on said driven shaft and meshing with said driving gear, a carrier for said driven shaft mounted for oscillatory movement about the axis of said driving shaft, means on said driving shaft and connections to oscillate said carrier, a crank on said driven shaft. and a pitman actuated by said crank and connected to impart circular movement to said loop-taker.

4,, In a buttonhole sewing machine, a frame, a turret journaled in said frame, an oscillatory shuttle and bobbin mounted in said turret, an endwise reciprocatory shuttle-actuating rod mounted in and coaxially with said turret, a slideblock mounted in said frame and connected to said rod, a driving shaft, a gear on said shaft, a driven shaft, a driven gear carried thereby of one-half the size of and meshing with said driving gear, a. carrier for said driven shaft journaled for oscillatory movement about the axis of said driving shaft, a crank on said driven shalt, a pitman connection between said crank and slideblock, an eccentric on said. driving shaft, and a lever connection between said eccentric and carrier Patent No. 2,107,271.

5. A needle-bar, a yoke at the lower end of said needle-bar, a cross-pin carried by said yoke, a needle-clamp-block slidably mounted on said cross-pin, a rotary bushing in which said needlebar is journaled, spaced arms extending downwardly from said bushing, a cross-pin carried by said arms, one of said arms having a guideway for said yoke, a guide-block slidably mounted on said last-mentioned cross-pin and formed with a vertical guideway for said needle-clamp-block, and means carried by said bushing for reciprocating said guide-block on its supporting cross-pin.

JOSEPHINE W. ALLEN, Administratrix of the Estate of Edward B. Allen,

Deceased.

MAURICE D. KNOX. HAROLD C. FAULKNER.

CERTIFICATE OF CORRECTION.

ry a, 1958.

JOSEPHINE W. ALLEN, ADMINISTRATRIX 0F EDWARD B. ALLEN, DECEASED, ET AL.

It is hereby certified that error appears in the above numbered patent requiring; correction as follows: cut," first occurrence,

the Patent Office In the grant, line 5, after "Connectiinsert the words and comma and Maurice D. Knox, of Devon, and that the said Letters Patent should be'readwith this rection therein that the same may conform to the Signed and sealed this 8th day of March, A. D. 1958.

(Seal) Henry Van Arsdale, Acting Commissioner of Patents.

crank and connected to impart circular movement to said loop-taker.

4,, In a buttonhole sewing machine, a frame, a turret journaled in said frame, an oscillatory shuttle and bobbin mounted in said turret, an endwise reciprocatory shuttle-actuating rod mounted in and coaxially with said turret, a slideblock mounted in said frame and connected to said rod, a driving shaft, a gear on said shaft, a driven shaft, a driven gear carried thereby of one-half the size of and meshing with said driving gear, a. carrier for said driven shaft journaled for oscillatory movement about the axis of said driving shaft, a crank on said driven shalt, a pitman connection between said crank and slideblock, an eccentric on said. driving shaft, and a lever connection between said eccentric and carrier Patent No. 2,107,271.

5. A needle-bar, a yoke at the lower end of said needle-bar, a cross-pin carried by said yoke, a needle-clamp-block slidably mounted on said cross-pin, a rotary bushing in which said needlebar is journaled, spaced arms extending downwardly from said bushing, a cross-pin carried by said arms, one of said arms having a guideway for said yoke, a guide-block slidably mounted on said last-mentioned cross-pin and formed with a vertical guideway for said needle-clamp-block, and means carried by said bushing for reciprocating said guide-block on its supporting cross-pin.

JOSEPHINE W. ALLEN, Administratrix of the Estate of Edward B. Allen,

Deceased.

MAURICE D. KNOX. HAROLD C. FAULKNER.

CERTIFICATE OF CORRECTION.

ry a, 1958.

JOSEPHINE W. ALLEN, ADMINISTRATRIX 0F EDWARD B. ALLEN, DECEASED, ET AL.

It is hereby certified that error appears in the above numbered patent requiring; correction as follows: cut," first occurrence,

the Patent Office In the grant, line 5, after "Connectiinsert the words and comma and Maurice D. Knox, of Devon, and that the said Letters Patent should be'readwith this rection therein that the same may conform to the Signed and sealed this 8th day of March, A. D. 1958.

(Seal) Henry Van Arsdale, Acting Commissioner of Patents. 

